1. Field of the Invention
The present invention relates to a producing method of a wired circuit board, to be specific, to a producing method of a wired circuit board that is preferably used as a suspension board with circuit.
2. Description of Related Art
A suspension board with circuit including a metal supporting board, an insulating base layer that is formed thereon, and a conductive pattern that is formed thereon has been known. The suspension board with circuit is mounted with a magnetic head and is used in a hard disk drive and the like. The conductive pattern is connected to the magnetic head and an external board, and an electrical signal is transmitted between the magnetic head and the external board via the conductive pattern.
In addition, there has been proposed the suspension board with circuit in which the conductive pattern is ground connected via a ground terminal that is conducted to the metal supporting board in order to reduce a noise caused by a difference in potential between the metal supporting board and the conductive pattern (ref: for example, Japanese Unexamined Patent Publication No. 2006-12205).
In the suspension board with circuit in Japanese Unexamined Patent Publication No. 2006-12205, the insulating base layer having a base opening is formed on the metal supporting board; next, a metal thin film (seed film) is formed on the metal supporting board that is exposed from the base opening; and subsequently, the ground terminal is formed on the metal thin film by a plating. That is, the ground terminal is formed on the metal supporting board via the metal thin film.